US Bridges

RTE 20 over Unadilla River

Good

Herkimer County, New York · 1 MI W JCT US 20 & SH 51 · Structure no. 000000001015840

Built
2005
20 years old
Condition
Good
inspected October 2023
Type
Box Beam or Girders - Multiple
Concrete
Length
67 ft
1 main span
Daily traffic
2,612
2016 count
Owner
State
State Highway Agency

About this bridge

RTE 20 over Unadilla River is a concrete box beam or girders - multiple carrying RTE 20 over Unadilla River in Herkimer County, New York. It was built in 2005, so it is 20 years old, younger than the New York average of 53 years.

The most recent inspection reported to the Federal Highway Administration rates it in good condition with a lowest component rating of 7 out of 9. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

It carries about 2,612 vehicles a day, roughly 12% of them trucks, projected to reach 2,817 by 2041. The structure is 67 ft (20.4 m) long and 43 ft wide. If it were closed, the detour would be 39.8 mi (64 km).

CarriesRTE 20
CrossesUnadilla River
Location1 MI W JCT US 20 & SH 51
RouteU.S. Route 20
Coordinates42.88888, -75.15641
Functional classRural Principal Arterial - Other

Condition and inspection

Good

All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted.

ComponentRatingMeaning
Deck7 GoodSome minor problems.
Superstructure9 ExcellentNo problems noted.
Substructure8 Very GoodNo problems noted.
Channel and channel protection8 Very GoodNo problems noted.
Last inspectionOctober 2023
Inspection intervalevery 24 months
Operating statusOpen, no restriction
ScourFoundations stable; scour above top of footing
Structural evaluation8: Equal to present desirable criteria
Deck geometry5: Somewhat better than minimum adequacy to tolerate being left in place as is
Waterway adequacy6: Equal to present minimum criteria
Approach roadway alignment8: Equal to present desirable criteria
Operating rating110.1 US tons
Inventory rating66 US tons

Structure

MaterialConcrete
DeckConcrete, cast-in-place
Main spans1
Design loadHS 25 or greater
Structure length67 ft (20.4 m)
Longest span62 ft (18.9 m)
Deck width43 ft (13 m)
Roadway width39 ft (12 m)
Vertical clearance over deckUnrestricted

Traffic and service

Average daily traffic2,612 (2016)
Projected traffic2,817 by 2041
Trucks12%
Lanes on structure2
Traffic directionTwo-way traffic
CarriesHighway
CrossesWaterway
Detour if closed39.8 mi (64 km)
TollOn a free road
National Highway SystemYes

Ownership and planned work

OwnerState Highway Agency
Maintained byState Highway Agency
Historic statusNot eligible for the National Register of Historic Places
Work proposedWidening with deck rehabilitation or replacement
Estimated improvement cost$971,000 (2024 estimate)
NavigationNo navigation control on waterway

Frequently asked questions

When was RTE 20 over Unadilla River built?

It was built in 2005, making it 20 years old in 2025.

What condition is RTE 20 over Unadilla River in?

The National Bridge Inventory rates it in good condition. All primary components (deck, superstructure, substructure, or culvert) are rated 7 or higher. No significant problems were noted. The last reported inspection was in October 2023.

How much traffic does RTE 20 over Unadilla River carry?

About 2,612 vehicles per day (2016 count), of which roughly 12% are trucks.

How long is RTE 20 over Unadilla River?

The structure is 67 ft (20.4 m) long with a longest span of 62 ft (18.9 m) and a deck 43 ft wide.

Who owns RTE 20 over Unadilla River?

It is owned by the State Highway Agency.